Electropneumatic brake



W. V. TURNER.

ELECTROFNEUMATIC BRAKE.

APPLICATLQ! menncr. 25. ms.

1,339,681, Patented May 11,1920.

INVENTOH UNITED STATES PATENT OFFICE.

WALTER V. TURNER, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE WESTING- HOUSE AIR BRAKE COMPANY, OF WILMERDING, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

ELECTROPNEUMATIC BRAKE.

Specification of Letters Patent.

Patented May 11, 1920.

To all whom it may concern Be it known that I, WALTER V. TURNER, a citizen of the United States, residing at Vilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Electropneumatic Brakes, of which the following is a specification.

This invention relates to fluid pressure brakes, and more particularly to a brake adapted to be controlled electrically as well aslpneumatically.

t has heretofore been proposed to provide a brake equipment having means for controlling the brakes electrically and by straight air and in which the straight air pipe is utilized for supplying and releasing fluid under pressure to and from the brake cylinder when the brakes are controlled e ectrically.

With the above type of brake equipment, if the straight air pipe should break or if the straight air pipe hose couplings should part, the brakes could not be applied electrically, or if already applied, the braking pressure would be lost.

The principal object of my invention is to rovide means for overcoming the above difhculty.

If the equipment is provided with an electrically controlled release valve, the improvement also prevents loss of air in case the release valve should happen to stick open.

In the accompanying drawing, the single figure is a diagrammatic view, partly in section, of a car air brake equipment embodying my invention.

As shown in the drawing, the equipment may comprise an emergency valve device 1, an emergency brake pipe 2, a straight air pipe 3, a combined bra e valve and switch 4, one at each end of the car, an electric application and release valve device 5, a brake cylinder 6, a main reservoir 7, and a double check valve device 8.

The emergency valve device 1 may comprise a casing having a piston chamber 9, connected by passage 10 to brake pipe 2, and containmg a piston 11, and having a valve chamber 12, connected to main reservoir ipe 13, and containing a slide valve 14, a apted to be operated by piston 11.

The electric application and release valve device 5 may comprise a release magnet 15 for operating a release valve 16, an application magnet 17, for operating a pilot valve 18, and a relay valve 19, adapted to be controlled by the pilot valve 18.

The double check valve device 8 may comprise a casing having a piston chamber 20, containing a piston 21., a piston chamber 22, containing piston 23, connected to piston 21, and an intermediate valve chamber 24, containing a slide valve 25.

In operation, the valve chamber 12 of the emergency valve device 1 is charged with main reservoir pressure, supplied through pipe 13, and fluid flows from said valve chamber, through the usual feed groove around piston 11 to piston chamber 9, and thence to the brake pipe 2.

Fluid from the main reservoir also flows from pipe 13, through a passage 26 to the inner face of the relay valve 19 and thence through a restricted port 27 in the valve, to the opposite side. Passage 28 being closed by the pilot valve 18, the fluid pressures upon opposite sides of the relay valve 19 equalize, permitting the spring 29 to hold the valve closed.

In the release position of the emergency valve device 1, the brake cylinder 6 is connected, through pipe 30 passage 31, cavity 32 in slide valve 14, and passage 33, with a pipe 34, leading to the double check valve device 8.

If it is desired to effect an electric application of the brakes, the a plication magnet 17 is energized to open the pilot valve 18, while the release magnet 15 is denergized, to close the release valve 16. The opening of valve 18 operates to vent fluid from the spring chamber of the relay valve 19, so that said valve is opened and fluid is supplied from the main reservoir 7, through passage 26 to passage 35 and thence to piston chamber 20 of the double check valve device 8.

The double check valve will be shifted by the fluid pressure supplied to the piston chamber 20 to the position shown in the drawing, if not already in that position, and fluid will then flow through port 36 to passage 37 and pipe 34. From pipe 34 fluid flows through cavity 32 in the emergency slide valve 14 to the brake cylinder 6.

The brakes may be electrically released by energizing the release magnet 15, so as to open the release valve 16 and thus vent fluid from the brake cylinder, through passage to exhaust port 37.

The brakes maybe applied by straight air, by moving-the brake valve to straight air application position, in which fluid is supplied to the straight air pipe -3 and thence to pistonchamber 22 of the double check valve device 8. The double check valve is then shifted tothe left, so thatipiston chamber 22 is opened to passage 37, permitting fluid to flow to the pipe 34 and thebrake cylinder6, to effect a straight ,air application of the brakes.

In order to assist in maintaining the double check valve in its different positions a cavity 38in the slide valve25 is adapted to connect passage with exhaust port 39 when the double check valve is in its right hand position, or passage :elhleading to piston chamber 20, with said exhaust port when the check valve is in its left hand position.

If the straight air pipe 3 should break or itshhose connections should part,the double check valve device 8 will prevent the loss be shifted to emergency position, in which passage 31 is openechto valve chamber :12,

so that fluid isvsupplied fromthe mainireservoir to the brake cylinder.

In theelnergency position of slide valve 14, cavity-32 cenneetspassage 10, leadingto brake pipe 2, with passage 33, sothat upon releasing the brakes after an. emergency: applieation a prompt release may be secured by energizing the applicationmagnetlT, so as'to eifect the supply of fluid underipressure to pipe 34 and thence through cavity 32 to the brake pipe, thus quickly rechargiingtheibfakepipfi to a pressure sufiicien to effect the release.

It will now be notedsthat ii thi as as well as these previously mentioned, fluid will be prevented from escaping through pipe S-ttothe straight air pipe, in easethe straight air pipe ,is broken.

w.ters Patent, is u ,1. :In afluid pressure brake, the combinatien with a brake cylinder, brake pipe,

straight air pipe, and anel-nergency valve device operateda pqn a reduction ,in bnake pipe pressure for supplying fluid to the brake cylinder, of electrically controlled means forlsupplying fluid tothebrake cylinder, anrla check valve device for controh ling connnunication from the brake c linder to the exhaust, from said electrical y controlled means to the brake cylinder, and from the straight? air pipe to ;the brake cyllinder.

'2. In a fluid, pressure brake, the combination ,With a brake cylinder, ;a straight ,air rp pesa lectr cal y een led m ans for supplying and releasingfluid to and from the'bnake cylinder, ofia doublacheck valve device. op rated y th fi w. aifluid from the straight air pipe to the brake cylinder for cutt ng i wmmunica thraug wh fluid; is; released fromlthe brake cylinder and by the-flow of air-inveleetrisfiilly apply ng the brake o setting Qfi ommuni atio from the straight air pipe to the brake .cylinderl-nztsst m ny he eo ,I have h r 1nto, .se

my hand.

WALTER V. TURNER. 

